diff --git a/editions/tw5.com/tiddlers/filters/examples/subfilter Operator (Examples).tid b/editions/tw5.com/tiddlers/filters/examples/subfilter Operator (Examples).tid
index af63b42d2..eac8828a3 100644
--- a/editions/tw5.com/tiddlers/filters/examples/subfilter Operator (Examples).tid	
+++ b/editions/tw5.com/tiddlers/filters/examples/subfilter Operator (Examples).tid	
@@ -1,8 +1,30 @@
 created: 20181031175129475
-modified: 20181031175129475
+modified: 20211030223407188
 tags: [[subfilter Operator]] [[Operator Examples]]
 title: subfilter Operator (Examples)
 type: text/vnd.tiddlywiki
 
-<<.operator-example 1 "[subfilter[one two three]addsuffix[!]]">>
-<<.operator-example 2 "[subfilter{$:/StoryList!!list}]">>
+\define recent-mods() [has[modified]!sort[modified]limit[5]]
+\define display-variable(name)
+''<$text text=<<__name__>>/>'': <code><$text text={{{ [<__name__>getvariable[]] }}}/></code>
+\end
+
+Literal filter operands can be used, but such cases are better rewritten without using <<.op subfilter>>:
+<<.operator-example 1 "[subfilter[one two three]addsuffix[!]]" "same as `one two three +[addsuffix[!]]`">>
+
+The <<.op subfilter>> operator can be used to dynamically define parts of a [[filter run|Filter Run]]. This is useful for sharing a common pieces of a filter across multiple filters.
+
+For example, this variable:
+
+* <<display-variable recent-mods>>
+
+can be used in one filter like this:
+
+<<.operator-example 2 "[tag[Filter Operators]subfilter<recent-mods>addsuffix[!]]" "same as `[tag[Filter Operators]has[modified]!sort[modified]limit[5]addsuffix[!]]`">>
+
+and in another similar filter like this:
+<<.operator-example 3 "[tag[ActionWidgets]subfilter<recent-mods>addprefix[!]]">>
+
+Variables are not the only way to define dynamic subfilters. [[Text references|TextReference]] can be used to load a subfilter from a tiddler field (see also [[Filter Parameter]]):
+<<.operator-example 4 "[subfilter{$:/StoryList!!list}limit[5]]">>
+<<.operator-example 5 "[subfilter{$:/StoryList!!list}subfilter<recent-mods>]">>
diff --git a/editions/tw5.com/tiddlers/filters/subfilter Operator.tid b/editions/tw5.com/tiddlers/filters/subfilter Operator.tid
index a02c1f125..30a49a122 100644
--- a/editions/tw5.com/tiddlers/filters/subfilter Operator.tid	
+++ b/editions/tw5.com/tiddlers/filters/subfilter Operator.tid	
@@ -1,6 +1,6 @@
 caption: subfilter
 created: 20181031175129475
-modified: 20181031175129475
+modified: 20211030223407188
 op-input: a [[selection of titles|Title Selection]] passed as input to the subfilter
 op-neg-input: a [[selection of titles|Title Selection]] passed as input to the subfilter
 op-neg-output: those input titles that are <<.em not>> returned from the subfilter  <<.place S>>
@@ -12,7 +12,7 @@ tags: [[Filter Operators]] [[Field Operators]] [[Selection Constructors]] [[Nega
 title: subfilter Operator
 type: text/vnd.tiddlywiki
 
-<<.from-version "5.1.18">> Note that the subfilter operator was introduced in version 5.1.18 and is not available in earlier versions.
+<<.from-version "5.1.18">> Note that the <<.op subfilter>> operator was introduced in version 5.1.18 and is not available in earlier versions.
 
 <<.tip " Literal filter operands cannot contain square brackets but you can work around the issue by using a variable:">>
 
@@ -24,4 +24,6 @@ type: text/vnd.tiddlywiki
 
 <<.tip "Compare with the similar [[filter|filter Operator]] operator which runs a subfilter against each title, returning those titles that return a non-empty list (and discards the results of the subfilter)">>
 
+The <<.op subfilter>> operator will act as a [[constructor|Selection Constructors]] whenever the filter defined by its operand is a [[constructor|Selection Constructors]]. Otherwise, it will act as a [[modifier|Selection Constructors]].
+
 <<.operator-examples "subfilter">>